DESCRIPTION OF THE PRIOR ART
Kopchik has disclosed in Belgian Pat. No. 848,486 of May 18, 1977 certain novel polyglutarimides prepared by a novel process and having improved properties over any previous polyglutarimides.
For many applications for engineering thermoplastics, impact strengths as measured by the notched Izod and the Gardner VHIT tests must meet certain standards. One benchmark is a product of the General Electric Company sold under the trademark Noryl 731 and comprised of a polyphenylene oxide and polystyrene blend, having a notched Izod of 3 and a Gardner VHIT of 100 inch-pound at 25.degree. C.
Although Kopchik did disclose that impact modifiers can be used in his novel polyglutarimides to improve their impact strength, no one prior to my invention was able to achieve an impact strength in polyglutarimides equivalent to the Noryl 731 benchmark for impact strength.
Therefore, it is an object of the present invention to improve the notched Izod and Gardner VHIT impact strengths of polyglutarimides so as to make them competitive with other engineering thermoplastics.
A further object is to provide improved polyglutarimides.
A still further object is to provide a process for achieving improved polyglutarimides.